L6726 Summary of contents

... Parameters are set independently which means easy adaptation for various market needs. The UTC L6726 is developed for using with CMOS-type dialer ICs. A separate DTMF input is switched when the circuit is muted, and an adjustable DC supply is provided for feeding an external CMOS device ...

... TI Input of transmit amplifier. Input impedance 17kΩ±20% The positive power supply terminal for most of the circuitry inside the UTC L6726 (about 1mA current 4 +C consumption).The +C-PIN shall be connected to a decoupling capacitor of 47µF to 150µF When low, speech circuit is muted and the DTMF input is enabled ...

... L6726 FUNCTIONAL DESCRIPTION The gain of the transmitting and receiving amplifiers are continuously and euqually changed with the line length. The starting point for the gain regulation is externally set .The gain regulation can be cut-off externally, see table under gain regulation below. The outputs of the transmitting and receiving amplifiers have internals limitations of the output amplitudes. ...

... L6726 APPLICATION INFORMATION Refer to figure 6. Gain regulation (R1, R2): These resistors set the starting point for the gain-and side tone regulation. Input impedance pin 6 is about 5.5 kΩ±20%. Below are some typical values for R1 and R2, for some different supplies from telephone stations. ...

... L6726 APPLICATION INFORMATION(Cont.) R15: This resistor is used to set the driving capability of the receiver output amplifier. Common values are 0 Ω Ω. Setting it for low driving capability results in function at lower line current. Breaking up pin 16 will give lower power consumption and total mute of the receiver when muting the circuit. Disconnecting pin 15 will of cause also give total receiver mute ...

... L6726 APPLICATION INFORMATION(Cont.) DESIGN PROCEDURE: 1. Circuit impedance to the line. 2. DC-characteristic 3. Gain regulation. 4. Transmitter gain and frequency response. 5. Receiver gain and frequency response. 6. Side-tone. 7. Components to suppress radio interference, specially the wires up to the handset. Others: The circuit can be placed either in the telephone or in the handset. ...

... L6726 UTC assumes no responsibility for equipment failures that result from using products at values that exceed, even momentarily, rated values (such as maximum ratings, operating condition ranges, or other parameters) listed in products specifications of any and all UTC products described or contained www.DataSheet4U.com herein. UTC products are not designed for use in life support appliances, devices or systems where malfunction of these products can be reasonably expected to result in personal injury ...